Various cardiothoracic surgeries, including coronary artery bypass grafting (CABG), heart valve repair or replacement, septal defect repair, pulmonary thrombectomy, atherectomy, aneurysm repair and correction of congenital defects, generally require pulmonary bypass (CPB), and cardiac arrest. Traditionally, these surgeries are performed through a mid-sternotomy incision. Such an open chest approach entails prolonged hospitalization and rehabilitation by the patient due to significant trauma to the chest wall. Minimally invasive surgical procedures which use an endoscopic approach have been developed to reduce the morbidity and mortality of the surgery, eliminating the need for a gross thoracotomy. More specifically, small incisions are made on a patient's chest wall, often in the intercostal space, to allow insertion of various instruments to reach the heart and great vessels. In a port-access approach during CABG surgery, arterial cannulation for CPB and cardioplegia delivery for cardiac arrest an be achieved by using endoscopic devices and techniques through a minimal access port in the intercostal space.
New devices and methods are therefore desired to facilitate the performance of minimally invasive CABG. Before CPB can be initiated, incisions are made in the right atrium and the aorta to allow insertion of venous and arterial cannulas. It is often difficult, however, to insert a cannula through various tissue layers to reach the aorta, due to its lack of rigidity. Moreover, it is particularly difficult to insert a cannula having a bent distal end through a narrow intercostal passage into the heart or great vessels. In addition, the cannula may be punctured by the sometimes-calcific arterial wall. A need, therefore, exists for a cannula system which provides easy penetration of a bent cannula through a small incision in tissue layers, and protection of the cannula during its deployment in the aorta.